Class Informer for Binary Ninja

April 30, 2026 ยท View on GitHub

Class Informer is a native port of the well known IDA Pro plugin by Sirmabus / kweatherman. It automates the tedious process of finding and reconstructing C++ class hierarchies in MSVC-compiled binaries, saving you from the manual "vtable-hunting" grind.

Features

  • RTTI Analysis: Automatically scans for MSVC Run-Time Type Identification data, including CompleteObjectLocator, TypeDescriptor, and ClassHierarchyDescriptor.
  • Virtual Table Discovery: Locates vftables using a two-pass scanning approach: COL-anchored and heuristic segment sweeps.
  • Hierarchy Reconstruction: Reconstructs complex inheritance patterns, including Single, Multiple, and Virtual inheritance.
  • Automatic Annotation: Automatically renames identified structures and adds descriptive comments for class names and inheritance labels.
  • Native UI Results Pane: Includes a searchable, sortable sidebar widget to browse discovered classes and navigate instantly to vftables.

File Structure

The plugin is organized into the following components:

FileDescription
__init__.pyThe main entry point that registers commands and handles background task threading.
plugin.jsonMetadata and configuration for the Binary Ninja plugin manager.
rtti.pyContains the core logic for scanning and parsing MSVC RTTI structures.
ui.pyImplements the native SidebarWidget and results table using PySide6.
vftable.pyHandles the discovery, validation, and annotation of virtual function tables.

Installation

  1. Find your Binary Ninja user plugins directory.
  2. Copy the plugin folder (containing plugin.json) into that directory.
  3. Restart Binary Ninja or use the Plugins -> Refresh Plugins menu.

Usage

Once installed, access the tool via the Plugin Command menu or the command palette:

  1. Run Scan: Select Class Informer \ Run Scan or press the "Scan" button in the Class Informer window.
    • This launches a background thread via __init__.py to keep the UI responsive while it processes the binary.
  2. Browse Results: A "Class Informer" sidebar widget (powered by ui.py) will appear.
    • Filter: Search by class name to narrow down the results.
    • Navigate: Double-click any row to jump directly to the vftable in the Linear View.
  3. About: Check Class Informer \ About for version details and credits.

Video

https://www.youtube.com/watch?v=VdoSjZBfS5U

Image

screenshot

Technical Details

RTTI & Vftable Logic

The scanning logic in rtti.py and vftable.py mirrors the original IDA Pro implementation:

  • Pass 1 (COL-anchored): Validates the pointer directly following a known CompleteObjectLocator.
  • Pass 2 (Segment Sweep): Uses a heuristic sweep of data segments to find tables missed by initial RTTI analysis.
  • Architecture Support: Seamlessly handles both 32-bit (absolute addresses) and 64-bit (relative 32-bit offsets) binaries.

Credits & License